1) Preheat the oven to 225C/450F/Gas 8. 2) Lay the potatoes over the bottom of a greased 23cm flan dish. 3) Top with the anchovies and then the tomatoes. 4) Whisk the eggs with black pepper and pour over the other ingredients. Sprinkle with the marjoram. 5) Bake in the oven for 20–25 minutes until set. 6) Whisk the oil and lemon juice together, season to taste. 7) Serve a slice of the tart with a handful of rocket and the oil and lemon dressing.